Process for producing chloro-vinyl fibers having modified light reflection

Claim 2

A PROCESS FOR PREPARING CHLOROVINYL FIBERS HAVING REDUCED LIGHT REFLECTION, SAID PROCESS CONSISTING ESSENTIALLY OF INCORPORATING INTO A SPINNING SOLUTION OF VINYL CHLORIDE POLYMER SELECTED FROM THE GROUP CONSISTING OF (A) HOMOPOLYMERS OF VINYL CHLORIDE AND COMPLYMERS OF VINYL CHLORIDE CONTAINING AT LIGHT 80% BY WEIGHT OF VINYL CHLORIDE OBTAINED BY POLYMERIZATION AT A TEMPERATURE GREATER THAN 0*C; (B) HOMOPOLYMERS OF VINYL CHLORIDE AND COMPLYMERS VINYL CHLORIDE CONTAINING AT LEAST 80% BY WEIGHT OF VINYL CHLORIDE OBTAINED BY POLYMERIZATION AT A TEMPERATURE OF 0*C OR BELOW 0*C (C) MIXTURES OF SAID POLYMERS OR COPOLYMERS (A) AND 8B); (D) HOMOPOLYMERS AND COMPOLYMERS OF VINYL CHLORIDE AS DEFINED UNDER ITEMS (A) AND (B) WHICH HAVE BEEN POST-CHLORINATED; (C) MIXTURES OF SAID POLYMERS (D) AND (A) OR/AND (B9 IN ANY COMBINATION; AND (F) MIXTURES OF SYNDIOTACTIC POLYVINYL CHLORIDE WITH POSTCHLORINATED ATACTIC POLYVINYL CHLORIDE, ABOUT 2 TO 15% BY WEIGHT BASED ON THE WEIGHT OF SAID POLYMER, OF A WHITE OR COLORLESS INORGANIC METAL SALT SELECTED FROM THE GROUP CONSISTING OF POTASSIUM SULPHATE, SODIUM SULPHATE, POTASSIUM BROMATE AND SUDIUM BROMATE HAVING A DENSITY GREATER THAN 2 G/CC AND A PARTICLE SIZE OF UP TO ABOUT 30 MICRONS, EXTRUDING THE FIBERS, REMOVING FROM THE SURFACE OF THE THUS EXTRUDED FIBERS AT LEAST A PORTION OF SAID ADDED SALT BY CONTACTING SAID FIBERS WITH A SOLVENT FOR THE ADDED SALT, STRETCHING THE EXTRUDED FIBERS AND THEN DRYING AND HEAT STABILIZING THE STRECHED FIBERS.

Claim 3

A process for preparing chlorovinyl fibers having reduced light reflection, said process consisting essentially of incorporating into a spinning solution of a vinyl chloride polymer selected from the group consisting of (a) homopolymers of vinyl chloride and copolymers of vinyl chloride containing at least 80% by weight of vinyl chloride obtained by polymerization at a temperature greater than 0*C; (b) homopolymers of vinyl chloride and copolymers of vinyl chloride containing at least 80% by weight of vinyl chloride obtained by polymerization at a temperature of 0*C or below 0*C; (c) mixtures of said polymers or copolymers (a) and (b); (d) homopolymers and copolymers of vinyl chloride as defined under items (a) and (b) which have been post-chlorinated; (e) mixtures of said polymers (d) and (a) or/and (b) in any combination; and (f) mixtures of syndiotactic polyvinyl chloride with post-chlorinated atactic polyvinyl chloride, about 2 to 15% by weight, based on the weight of said polymer, of a white or colorless inorganic metal salt selected from the group consisting of potassium sulphate, sodium sulphate, potassium bromate and sodium bromate and having a density greater than 2 g/cc and a particle size of up to about 30 microns, extruding the fibers, removing from the surface of the thus extruded fibers at least a portion of said added salt by contacting said fibers with a solvent for the added salt, stretching the extruded fibers and then drying and heat stabilizing the stretched fibers.

Claim 4

A process for preparing chlorovinyl fibers having reduced light reflection, said process consisting essentially of incorporating into a spinning solution of a vinyl chloride polymer selected from the group consisting of (a) homopolymers of vinyl chloride and copolymers of vinyl chloride containing at least 80% by weight of vinyl chloride obtained by polymerization at a temperature greater than 0*C; (b) homopolymers of vinyl chloride and copolymers of vinyl chloride containing at least 80% by weight of vinyl chloride obtained by polymerization at a temperature of 0*C or below 0*C; (c) mixtures of said polymers or copolymers (a) and (b); (d) homopolymers and copolymers of vinyl chloride as defined under items (a) and (b) which have been post-chlorinated; (e) mixtures of said polymers (d) and (a) or/and (b) in any combination; and (f) mixtures of syndiotactic polyvinyl chloride with post-chlorinated atactic polyvinyl chloride, about 2 to 15% by weight, based on the weight of said polymer, of a white or colorless inorganic metal salt selected from the group consisting of potassium sulphate, sodium sulphate, potassium bromate and sodium bromate and having a density greater than 2 g/cc and a particle size of up to about 30 microns, extruding the fibers, removing from the surface of the thus extruded fibers at least a portion of said added salt by contacting said fibers with a solvent for the added salt, stretching the extruded fibers and then drying and heat stabilizing the stretched fibers.

Claim 5

The process of claim 1, wherein the solvent for said added salt is water.

Claim 6

The process of claim 1, wherein the vinyl chloride polymer is poly(vinyl chloride).